HowtoConnect
INPUT
STEREOOPERATION
Useshieldedcablestoconnectthesignalfrom
thepreamplifierorsignalsourcetothepower
amplifier.Tominimizethepossibiltyofhumthe
shieldedcablesshouldberunparalleltoeachother
orlooselytwistedtogether.Locatethecablesaway
fromspeakerleadsandACpowercords.Allconnec-
tionsaremadeonthebackpaneloftheMC2155.
Forstereooperation,theleftoutputofthe
preamplifiershouldbepluggedintotheLeftinput
jackofthepoweramplifier.Therightoutputofthe
preamplifiershouldbepluggedintotheRight
(Mono)inputjackofthepoweramplifier.
InstereooperationtheMODESWITCHmustbein
theSTEREOposition.
MONOPHONICORSINGLECHANNELOPERATION
Ashieldedcablefromthesignalsourceisplug-
gedintotheRight(Mono)inputjackoftheMC2155
only.TheMODESWITCHonthebackpanelofthe
amplifiermustbeplacedinoneoftheMONOposi-
tions.IntheMONOpositionstheoutputoftheright
channelinputamplifierisfedtobothleftandright
poweramplifiers.TheLeftINPUTisdisconnected.
OnlythesignalfedintotheRight(MONO)inputwill
beamplified.
BecertainthattheMC2155isneveroperatedin
thestereomodewiththeoutputsconnectedfor
monophonicoperation.ShouldtheMODESWITCH
beleftintheSTEREOpositionandtheoutputsre-
mainstrappedfora monoparallelload,onechannel
willattempttodrivetheotherwhichcauseshighcir-
culatingcurrentsandoverheating.
OUTPUT
BecertaintheloudspeakersconnectedtotheMC
2155arecapableofhandlingthepoweroutputofthe
amplifier.
Selectionofthepropergaugewiretoconnectthe
loudspeakerspreservesthequalityofsoundrepro-
ductionforwhichtheloudspeakershavebeende-
signed.Ifundersizewireisused,resistanceisadded
totheamplifier/loudspeakercombinationwhich
adverselyaffectstheperformance.Addedresis-
tancecausesdepreciationofdampingcharacteris-
tics,modificationoffrequencyresponseandreduc-
tioninpoweroutput.
Uselampcordorwirewithsimilarinsulationto
connectthespeakerstotheamplifier.Inallcases,
theleadstoandfromthespeakershouldbetwin
conductorortwistedtogether.Whenusing8 ohm
speakersandforthenormallyshortdistancesof
under30feetbetweentheamplifierandspeaker,#
18wireorlargercanbeused.Fordistancesover30
feetuselargerdiameterwire.Selectthecorrectsize
wirefromthechartbelow.Itisrecommendedthat
theDCresistanceofthespeakerleadsbelessthan
5%ofthespeakerimpedance.Resistanceofthe
leadsshouldbecomputedforthelengthofwireboth
toandfromthespeakerorspeakers.
Formultiplespeakeroperation,runseparate
leadsfromtheamplifiertothespeakers.
Wire
Gauge
18
16
14
12
10
MAXIMUMWIRELENGTHS
For4 OhmLoad
Feet
15
25
40
60
100
Meters
4.57
7.62
12.19
18.29
30.48
For8 OhmLoad
Feet
30
50
80
120
200
Meters
9.14
15.24
24.38
36.58
60.96
Wirelengthsaboverepresentthewireresistance
equalto5%ofthespeakerimpedance.
STEREOOPERATION
Checktheimpedanceofthespeakerwhichis
usuallyidentifiedonthespeakeritselforinthe
owner'smanual.Connecta leadfromthecommon
terminaloftheleftspeakertotheamplifierLEFT
OUTPUTterminalstripCOMmonscrew.Connect
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